1. Field of the Invention
The present invention relates generally to robotics design and control, and particularly to a computerized parallel kinematic machine trajectory planning method.
2. Description of the Related Art
Parallel Kinematic Machines (PKMs) have two basic advantages over conventional machines of serial kinematic structures. First, with PKM structures, it is possible to mount all drives on or near the base. This yields to large payloads capability and low inertia. Indeed, the ratio of payload to the robot load is usually about 1/10 for serial robots, while only ½ for parallel ones. Second, the connection between the base and the end-effector (EE) is made with several kinematic chains. This results in high structural stiffness and rigidity. However, the PKM architecture-dependent performance associated with strong-coupled non-linear dynamics makes the trajectory planning and control system design for PKMs more difficult compared to serial machines.
Another major issue for practical use of PKMs in industry is that for a prescribed tool path in the workspace, the control system should guarantee the prescribed task completion within the workspace, for a given set up of the EE (i.e., for which limitations on actuator lengths and physical dimensions are not violated).
Thus, a parallel kinematic machine trajectory planning method solving the aforementioned problems is desired.